Australian-Coins Forum

Non Numismatic Discussion => Chin Wag => Topic started by: JeffH on November 17, 2018, 01:21:47 PM

Title: I'm glad they sorted it out -used to worry me!
Post by: JeffH on November 17, 2018, 01:21:47 PM
The kilogram is now defined by setting Planck's constant as 6.62607015 x 10-34 kg·m²per second¯¹. (https://www.vox.com/science-and-health/2018/11/14/18072368/kilogram-kibble-redefine-weight-science)
Title: RE: I'm glad they sorted out -used to worry me!
Post by: Triggersmob on November 17, 2018, 05:05:29 PM
I find it funny that the yanks are the keeper of the kilogram, but don't even use it themselves. :)
Title: RE: I'm glad they sorted out -used to worry me!
Post by: nealeffendi on November 17, 2018, 05:25:06 PM
Seems to me that they have high intelligence but low common sense. If a metre has been accurately defined (as well as temperature) then a kilogram could be defined in terms of a theoretical sphere (or cube, rectangle etc) of a known substance  (perhaps platinum or other substance) of set dimensions at a set temperature. Such a theoretical object wouldn't lose mass and could be replicated as a real object at any time or any location.
Also have to question the sanity of boffins who claim that the fixing of a standard for the metre as the most exciting thing to ever happen in their careers. And I thought my career was boring.
Title: RE: I'm glad they sorted out -used to worry me!
Post by: JeffH on November 17, 2018, 06:01:04 PM
Quote from: 'Triggersmob' pid='117547' dateline='1542436529'I find it funny that the yanks are the keeper of the kilogram, but don't even use it themselves. :)

Interesting thing is when I went to university mumble, mumble years ago (OK 50 years ago) and studied electrical engineering, most of the textbooks were American and they were all metric units.
nealeffendi is basically correct but there are a lot of variables that have to be controlled to make that work. The new definition is actually simpler, albeit incomprehensible to about 99.8% of the population, and -most importantly- can be replicated anywhere.

Of course the fact that the standard (in Paris) kilogram has lost 50μg (micrograms) over the years is really important to the boffins. Completely irrelevant to everyone else.
Incidentally that mass (not weight, that is a different thing) loss is  0.000005%!
Title: RE: I'm glad they sorted out -used to worry me!
Post by: Goldseeker on November 18, 2018, 09:32:28 AM
Will it do much to the value of precious metals.   IE:   Gold, silver and the like.

If it makes the metals more valueable, yes.   If not, I am not interested.
Title: RE: I'm glad they sorted it out -used to worry me!
Post by: JeffH on November 18, 2018, 09:44:49 AM
Will have no effect on anything really, so consider yourself disinterested.
Title: RE: I'm glad they sorted it out -used to worry me!
Post by: Goldseeker on November 18, 2018, 12:02:39 PM
OK, will do.